Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/009—Electrical control of supply of combustible mixture or its constituents using means for generating position or synchronisation signals
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
  • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/0097—Electrical control of supply of combustible mixture or its constituents using means for generating speed signals
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2409—Addressing techniques specially adapted therefor
  • F02D41/2416—Interpolation techniques
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
  • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
  • G01P13/00—Indicating or recording presence, absence, or direction, of movement
  • G01P13/02—Indicating direction only, e.g. by weather vane
  • G01P13/04—Indicating positive or negative direction of a linear movement or clockwise or anti-clockwise direction of a rotational movement
  • G01P13/045—Indicating positive or negative direction of a linear movement or clockwise or anti-clockwise direction of a rotational movement with speed indication
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
  • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
  • G01P3/42—Devices characterised by the use of electric or magnetic means
  • G01P3/44—Devices characterised by the use of electric or magnetic means for measuring angular speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
  • F02D2200/101—Engine speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
  • F02D2200/1012—Engine speed gradient
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/04—Introducing corrections for particular operating conditions
  • F02D41/042—Introducing corrections for particular operating conditions for stopping the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits specially adapted for starting of engines
  • F02N11/0814—Circuits specially adapted for starting of engines comprising means for controlling automatic idle-start-stop
  • F02N11/0844—Circuits specially adapted for starting of engines comprising means for controlling automatic idle-start-stop with means for restarting the engine directly after an engine stop request, e.g. caused by change of driver mind
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2200/00—Parameters used for control of starting apparatus
  • F02N2200/02—Parameters used for control of starting apparatus said parameters being related to the engine
  • F02N2200/022—Engine speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2250/00—Problems related to engine starting or engine's starting apparatus
  • F02N2250/04—Reverse rotation of the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/20—Control related aspects of engine starting characterised by the control method
  • F02N2300/2006—Control related aspects of engine starting characterised by the control method using prediction of future conditions

Definitions

• the present invention relates to a method for estimating the speed of a motor in a predetermined position and more particularly to determine in advance a risk of reversal of the direction of rotation of said motor.
• the invention generally relates to internal combustion engines and more particularly engines of this type for motor vehicles.
• An internal combustion engine whether it is a spark ignition engine (Otto engine) or a compression ignition engine (diesel engine), generally rotates in the same direction of rotation. However, when the engine stops, before reaching its off position, the engine rotates in one direction and then the other in a swinging motion around its off position.
• spark ignition engine OEM engine
• compression ignition engine diesel engine
• flywheel consisting of two masses connected together by springs to improve driving comfort.
• Such flywheel is called double flywheel damper (DVA), or double mass flywheel or flywheel dual mass.
• DVA double flywheel damper
• a mass of such a flywheel is connected to the crankshaft, and thus to the pistons, and the other to the transmission (for example shaft gearbox primary), and thus to the vehicle. It is then necessary to avoid overloading the springs lying between the two masses to limit the mechanical stresses on them. It is thus preferable to avoid all cases where the two masses of the flywheel have opposite directions of rotation.
• the adverse cases identified are the cases where the engine stalls.
• the engine may be rotated in the opposite direction as the vehicle moves forward. In such a case, it should be avoided that large forces are exerted on the pistons.
• Document EP 1 462 638 relates to a method and a device for determining the evolution of a motor parameter, in particular the motor speed of the motor, by interpolation of a polynomial on a mobile window of size w, where w is the number of measurement data obtained in the window. This document therefore defines estimated values within the measurement window w.
• the problem at the origin of the present invention is to avoid having a combustion which would drive the motor in its opposite direction of rotation in order to limit the stresses between the masses of a flywheel of mass mass.
• the original idea of the inventors is then to predict the speed of rotation of the motor at a predetermined position thereof. Indeed, in this way, it is possible to anticipate a possible engine stall.
• the prediction of the speed of rotation of the engine at a given position thereof, particularly at low speed could also be useful when starting the engine, to save money. example the starter and stop it as soon as the speed conditions are met to allow the engine to run in good conditions.
• the prediction of the speed of rotation can also be used for the adjustment of the choke and act on the richness of the mixture of the combustion chambers.
• This speed prediction can also be envisaged in a vehicle comprising both an internal combustion engine and an electric motor, commonly called a hybrid vehicle, to anticipate stalling of the internal combustion engine and starting of the electric motor (with conditions ).
• the present invention thus aims to provide means for determining in advance a rotational speed of a motor, in a predefined position thereof.
• the invention can be used, for example, to predict an inversion of the direction of rotation of the motor and thus to avoid making a combustion which would cause the motor in its opposite direction of rotation. It can also be used for engine management in other applications, for example for low speed engine management.
• the present invention proposes in a novel way a method for estimating the engine speed of an internal combustion engine at a predefined position thereof, said engine comprising:
• engine management means comprising means for determining the angular position of the crankshaft, also called angular position of the engine, and a clock for determining the time interval between two successive passes of a tooth in front of the sensor; .
• said method comprises the following steps:
• the method defined here makes it possible to determine in advance a motor speed at an angular position of the engine to come. This estimate is valid in an interval in which the velocity increases or in an interval in which the velocity decreases.
• the estimate that is made is a function whose variable is the angular position of the motor (and not a temporal variable). This makes it possible to simplify the calculations and therefore to limit the load of the microprocessor in charge of them.
• the chosen points are any points of the curve. However, they are preferably, on the one hand, close enough to each other and, on the other hand, not too far from the point for which the speed estimate must be made.
• the first measurement point and the second measurement point are measurement points corresponding to measurements of the sensor for two successive teeth.
• the approximation of the speed of rotation with respect to the angular position is determined as being the degree-two curve passing through the two measuring points and having a velocity gradient variation defined from the measured velocity gradient.
• the polynomial estimate is calculated by considering that the variation of the velocity gradient is a constant corresponding to the variation of the velocity gradient between, on the one hand, the velocity gradient resulting from the first one. measuring point and the second measurement point and, on the other hand, the distinct velocity gradient determined.
• This velocity gradient variation is made with measuring points of which at least one is distinct from the first measurement point and the second measurement point.
• the measurement points used for this speed gradient variation may correspond to signals supplied by the sensor for two neighboring teeth but also for two more or less distant teeth.
• the present invention also proposes a method for predicting a reverse rotation of an engine, characterized in that it comprises the following steps:
• the engine speed is for example estimated close to a top dead center of the engine, that is to say within 10 ° of this top dead center, and preferably to said top dead center of the engine.
• the predetermined threshold is then for example between 240 and 360 rpm (or between 8 ⁇ and 12 ⁇ rad / s).
• the present invention also relates to a method for managing an engine, comprising the following steps:
• the engine management device will act on the fuel injection means so that the next injection (or a succession of injections in a very short interval) does not take place in the case of a diesel type engine and for a spark ignition engine (type Otto), it will act on the fuel injection and / or ignition of the engine.
• a method of managing an engine may also include the following step:
• the present invention also relates to a device for managing an engine, characterized in that it comprises means for implementing each of the steps of a method as described above.
• FIG. 1 is a graph illustrating the speed of rotation of an engine with respect to time when stalling
• FIG. 2 is another representation of the speed of the motor relative to its angular position during a stall of the four-cylinder engine, the abscissae of the curve being represented modulo 180 °, and
• Figure 3 is a graph such as that of Figure 2 and illustrates various embodiments of the present invention.
• the present disclosure relates to an internal combustion engine of the Diesel type or of the type with controlled ignition (Otto type).
• a motor comprises a motor unit, in which cylinders are machined, closed at one end by a cylinder head.
• cylinders are machined, closed at one end by a cylinder head.
• pistons connected via a connecting rod to a crankshaft.
• An inertia flywheel is mounted at one end of the crankshaft.
• the position of the crankshaft determines the position of the engine, that is to say that when this position is known, we know the position of all the pistons in the corresponding cylinders and the position of many other mechanical parts of the engine.
• the crankshaft having only one degree of freedom in rotation the position of the engine is then determined by an angular value, called the (angular) position of the engine.
• the engine considered operates according to a four-stroke cycle.
• the position of the motor can be defined modulo 720 °, that is to say two complete revolutions of 360 °.
• the crankshaft with a target having teeth regularly distributed at an angular periodicity P, a starting point being defined by a long tooth, corresponding for example to two teeth and to the interval between them, or by the absence of one or two teeth.
• a position sensor is associated with the target and counts the teeth that pass in front of it. The passage time between two successive teeth is also measured using the sensor and a built-in clock in an electronic engine management system. It is assumed later that the number of teeth N corresponds to 360 / P. Thus for teeth regularly distributed with an angular pitch of 6 °, we will consider that we have 60 teeth and we will not take into account the singularity defining the point of origin.
• the present invention is more particularly intended to be implemented with motors having a double mass flywheel.
• a flywheel has two masses connected to one another by springs. One mass is integral with the crankshaft and the other is secured to a transmission that transmits to the wheels, said drive wheels, the vehicle energy produced in the engine.
• the invention can, however, also be implemented with a "conventional" flywheel having a single rotating mass and associated with a clutch.
• FIG. 1 illustrates the speed of rotation V of an engine, expressed in revolutions per minute (rpm), as a function of time t (in seconds “s” or milliseconds “ms”) just before the engine stalls.
• the curve shown is in the form of slots because the measuring points are discrete.
• the abscissa is given directly by the position sensor while the speed is obtained by measuring the time between two passes of teeth in front of this sensor.
• the pitch between two teeth being constant, the speed is inversely proportional to the time which separates the detection of two successive teeth.
• Figure 2 illustrates in another way the speed variation when the engine considered stalls.
• This is a four-cylinder engine for which combustion occurs every 180 °.
• This type of motor has been chosen arbitrarily for purely illustrative and non-limiting purposes and it will be apparent to those skilled in the art that the invention also applies to engines with a different number of cylinders.
• an angular range of 0 ° to 180 ° In the case of a four-cylinder engine, at 180 ° two pistons arrive at their top dead center, for one at the end of exhaust of the corresponding combustion chamber and for the other at the end of compression of the air (Diesel engine) or gas mixture (Otto engine) in the corresponding combustion chamber.
• the piston at the end of the compression phase does not reach its top dead center and the compressed fluid in the corresponding chamber pushes it back.
• the piston then drives the crankshaft backwards.
• the engine management device does not know that the piston starts back driving with the crankshaft in reverse rotation, it will control a fuel injection and / or ignition as if the engine continued to rotate in its normal direction of rotation .
• the compression in the corresponding combustion chamber is sufficient, combustion will take place and will cause the motor in its opposite direction of rotation. This combustion generates stresses in the engine that are important and can be harmful, especially for a dual-mass flywheel.
• the present invention proposes in an original way to determine in advance the speed of rotation of an engine.
• This predetermination of the rotational speed of the engine could also find applications in the injection management and / or ignition for example when starting the engine or more generally at low speed.
• the idea behind the present invention is, from velocities and variations of velocities, to determine at a point B a projection of the rotational speed for an angular position to come, for example at next top dead spot or close to it.
• the rotation speed V of the engine is not determined according to a time variable but according to the angular position A of the engine.
• the rotational speed V is approximated by a second order polynomial function with respect to the angular position A of the motor.
• V '(A) a A + b where b is a real constant.
• V (A) 1 ⁇ 2 to A 2 + b A + c
• a first possibility is to take the last three measurements and to determine the degree two curve passing through these three points.
• the results obtained with real measurements do not allow a good and robust prediction and this possibility was not retained.
• the last measurement point to take account of the last speed measured the penultimate measurement point to take account of the last velocity gradient
• V (A n ) 1 ⁇ 2 to A n 2 + b A n + c
• V (A n-1 ) 1 ⁇ 2 to A n-1 2 + b A n-1 + c
• the velocity gradient calculated from two successive measurement points corresponds to the (approximate) velocity gradient at the midpoint between the two measurement points considered.
• V (A n ) this velocity gradient. So :
• V '(A n ) [V (A n ) - V (A n-1 )] / (A n - A n- i)
• V '(A n ) [V (An) - V (A n -i)] / P
• V "(A n ) [V (A n ) - V '(A n -i)] / P: as it follows from the above, this is the constant a (see equation 2 above).
• V "(A n ) has been carried out here on three successive measuring points (n-2), (n-1) and n, the first two points being used for the calculation of V '(A n-1 ) and the last two for the calculation of V' (A n ).
• V "(A n ) is the variation of the velocity gradient between a point (nf) and the point n.
• V "(A n ) [V (A n ) - V (A nf )] / P xf
• V (A n ) - V (A n-1 ) [1 ⁇ 2 a A n 2 + b A n + c] - [1 ⁇ 2 a A n-1 2 + b A n-1 + c]
• V (A n ) - V (A n-1 ) 1 ⁇ 2 a (A n 2 - A n-1 2 ) + b (A n - A n-1 )
• V (A) V (A n ) + [(V (A n ) -V (A n-1 )) (A - A n ) / P]
• Figure 3 is an illustration of curves obtained with different values of "f".
• the curve in solid line corresponds to the speed of the motor according to its angular position modulo 180 °.
• the dotted line curves show velocity estimation curves with different values of f. Note in this figure that the velocity estimated by the polynomial function is overestimated. Note also that when the engine is not stalling (two higher estimates), the curves corresponding to the estimated speed are very close to the measured speed curve (solid line) whereas when the engine is stalling and turning in the opposite direction ( third game curves in dotted lines, below the first two) the speed estimate is further from the measured curve.
• the engine rotational speed estimate is used here to try to predict whether the engine pistons have enough kinetic energy to pass the next top dead center. It should be noted here, as is apparent for example from Figure 3, that the rotational speed of the engine is not minimal at top dead center but a little after this position.
• the calculation will have to be done shortly before reaching the top dead center.
• the estimated speed (calculated) is compared to the threshold S. If the estimate is below the threshold, the risk of having a reverse rotation is very large.
• the invention proposes in this case to inhibit the fuel injection and / or the next ignition control which is programmed for the combustion chamber in which a gaseous mixture is compressed.
• the engine management system controls under certain conditions the calculation of the top dead center speed. Triggering of the calculation can be provided in the lower layers, also commonly known by the acronym BSW for Basic
• the pitch P is a constant for each motor.
• the simplified formula 10 is in turn memorized and executed by an application software (also known by the acronym ASW for Applicative Software).
• ASW Applicative Software
• the present invention is original in many ways. First, she proposes to predict a rotation speed. This makes it possible to anticipate a possible reverse rotation of the motor. In the known state of the art, the reverse rotation is generally detected more or less early but not anticipated as described above. Then, to predict the speed of rotation, it is chosen to express this speed with respect to the angular position of the engine (and not with respect to a time variable). This facilitates calculations and limits the computing load of the corresponding processor. Finally, the choice of approaching the velocity curve by a polynomial function of degree two and the manner of determining the corresponding constants taking into account the velocity gradient and its variation is also original.
• the present invention makes it possible to determine well in advance a possible rear rotation of the engine.
• An empirical rule provides that when a passage of teeth is at least 1, 3 times longer than the previous passage, then a rearward rotation is to be expected.
• the invention makes it possible to know well before the application of this rule of thumb whether a rearward rotation is to be expected.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)

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• 2012
  • 2012-09-21 FR FR1258868A patent/FR2995939B1/fr active Active
• 2013
  • 2013-08-26 RU RU2015114707A patent/RU2647878C2/ru active
  • 2013-08-26 IN IN1334DEN2015 patent/IN2015DN01334A/en unknown
  • 2013-08-26 CN CN201380049344.5A patent/CN104641087B/zh active Active
  • 2013-08-26 WO PCT/EP2013/002565 patent/WO2014044353A1/fr not_active Ceased
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